1. Field of the Invention
The invention concerns cosmetic dermal strips or patches which provide consumers with a color change indicator as a sensorial signal.
2. The Related Art
Cosmetics are often provided with consumer perceivable sensorial signals. Most common of these signals are fragrances. Pleasing odor is often the single most important attribute inducing re-purchase by a consumer. Other sensorial attributes are also significant in cosmetic chemistry. Skinfeel of a product is highly important. Creams, lotions, gels and pastes often are judged for their efficacy by the tacticity of their feel. Silky, non-residue leaving cosmetics are much preferred over tacky ones, and the consumer may relate those aesthetics to actual pharmacological performance.
Sometimes the sensorial attribute is that of temperature. Coolness is imparted to toothpastes and aftershave lotions through the presence of camphor, menthol or menthol derivatives such as menthol lactate. Some formulations signal efficacy through a temperature increase. Inclusion of capsaicin, an alkaloid extracted from capsicum, gives a brief temperature rise sensation to the human neural system.
Dermal patches or strips have recently become popular as delivery vehicle systems for cosmetic compositions. For instance, WO 98/42303 (Crotty et al.) describes a dry-to-the-touch keratotic plug remover strip. Upon wetting, the strip turns tacky and mobile. This product is placed on the bridge of the nose or other areas of the face requiring keratotic plug removal. Within a short time period, water evaporates from the wetted adhesive forming a dry film. The consumer must then peel the film from the face along with unwanted plugs bonded thereto. Amounts of water applied by the consumer may vary. Drying times are therefore also variable. A sensorial signal would be helpful for the consumer to know when to begin the peel removal.
Exothermic and endothermic reactions are other sources of temperature signaling. U.S. Pat. No. 5,861,440 (Gohla et al.) reports use of sugars, especially xylitol, for inducing a cooling sensation when contacted with water. Generation of exothermic heat is reported in U.S. Pat. No. 4,379,143 (Sherry et al.), U.S. Pat. No. 4,626,550 (Hertzenberg), U.S. Pat. No. 4,362,715 (Strianse et al.) and U.S. Pat. No. 3,250,680 (Menkart et al.). Each of these patents employ an aluminosilicate interacting with water to release momentary heat.
Other types of sensorial signals have been sought for incorporation into cosmetics. The signals should either provide an independently new effect or complement those which have traditionally been employed.
Accordingly, it is an object of the present invention to provide cosmetic products, especially dermal strips or patches with a new sensorial signal.
Still another object of the present invention is to provide cosmetic products, especially dermal strips or patches with a sensorial signal which may augment other sensory or emotive aesthetics of such products.
Yet another object of the present invention is to provide cosmetic products, especially dermal strips or patches which include a timing mechanism for application, rub-in or removal of the product from a consumer's skin.
These and other objects of the present invention will become more readily apparent from consideration of the following summary and detailed discussion.